Replacement of the battery on Xiaomi Redmi 4A: disassembly, battery selection and installation

Xiaomi Redmi 4A is one of the most popular budget smartphones of 2017, but even after 5-7 years of operation, the battery loses up to 70% of capacity. If your device suddenly turns off at 30% charge, discharges in an hour or requires recharging 2-3 times a day, it’s time to think about replacing the battery. In this article, we will discuss how to do it yourself without contacting the service center, and save up to 1500 rubles.

The process of replacing the battery with the Redmi 4A is a medium-sized one: it requires precision, a minimum set of tools and 30-40 minutes of time. The main advantage of the model is a removable back cover, which makes it easier to access internal components. However, there are pitfalls: fragile plumes, battery adhesive and the risk of damage to the flexible power button cable. We will describe each step in detail so that you avoid typical errors.

Important: If you've never disassembled a smartphone, practice on an unnecessary device or watch a video disassembly before you start work. The battery in the Redmi 4A is soldered to the board not directly, but is connected via a connector - this reduces the risk of short circuits when replacing, but requires caution when disconnecting.

Signs of a faulty battery on the Redmi 4A

Before you start replacing, make sure the battery is the problem.

• 🔋 The smartphone is turned off when 20-40% charge and only activated after connection to charging.
• ⚡ The battery life has been reduced to 2-4 hours of normal use (previously kept in place) 10-12 hours).
• 🔥 The phone gets very hot during charging or heavy use (games, video).
• 📉 In settings (Settings) → Battery → Battery condition) capacity shows less than 70% of the original (original capacity - 3120 mAh).
• 🔌 Charging is jerky: it quickly gains interest, then “hangs” on one value.

If you see 3 or more signs, the battery definitely needs to be replaced. In rare cases, a faulty power controller on the motherboard can cause similar symptoms, but this is already a task for the service center. Use applications like AccuBattery (revealing real capacity) or CPU-Z (voltage tests) to diagnose.

⚠️ Warning: If the smartphone is swollen (the body is deformed, the screen "steps away" from the frame) - immediately turn it off and do not turn it on! the bloated battery may ignite.

Replacement tools and materials

You need a minimal set of tools to work. Don't skimp on quality, cheap plastic blades can break and scratch the body.

A separate conversation on the battery: the original batteries from Xiaomi are more expensive (1000-1200 ₽), But they last longer. There are brands that are tested: ZOP Power, CAMBAT, Baseus. avoid "no-name" options for 300-400 ₽ — They often have an understated real capacity and can swell in a month.

Preparing the smartphone for disassembly

Before starting work, follow several mandatory steps:

1. Turn off your smartphone and remove it. SIM-card and memory card (if any).
2. Charge the battery to 30-50%. A fully discharged battery can "go into defense" and show no signs of life after connecting a new one.
3. Back up your data (Settings → Additional → Backup or via Mi Cloud).
4. Prepare the workplace: flat surface, good lighting, no carpets (static electricity!).

If the screen cracks or moves away from the body, cover it with tape to prevent the shrapnel from hurting your hands, and we also recommend wearing an antistatic bracelet (or at least periodically touching metal objects) to avoid damage to the components by static discharge.

Is the smartphone off?|Whether extracted SIM microSD?|Is the data backup done?|Is the battery charged to 30-50%?|Is the workplace ready?-->

⚠️ Warning: Don't take Redmi apart 4A When humidity is high (e.g. in the bathroom) or in a dusty room, moisture on the contacts can cause corrosion, and dust can short circuit.

Step-by-step instructions for replacing the battery

Now, to the process itself, follow the instructions in strict order.

1. Removal of the back cover

The lid on the Redmi 4A is mounted on the latches and two screws. Start at the bottom.

1. Insert a plastic blade into the gap between the lid and the body at the charging connector.
2. Carefully swipe along the side faces, snapping the clamps. Don't force the lid, it should come off with a slight crack.
3. After disconnecting the latch, lift the lid up (it is connected to the fingerprint scanner plume).
4. Unscrew the two screws with a PH00 cross screwdriver and remove the lid completely.

If the lid doesn't lend itself, heat it up a little with a hair dryer (temperature no higher than 60°C) - the plastic will become softer. Don't use metal tools so as not to scratch the body!

2. Disconnection of the plumes

Under the lid, you'll see:

• 🔋 Battery (black rectangle with connector).
• 📱 Motherboard (green board with chips).
• 🎛 Power button plume (thin black cable at the top edge).

First, unplug the battery connector: put it on the side of the shoulder blade and pull it up. Then gently unplug the power button plume (it's brittle!). If the plume is glued, drop some isopropyl alcohol on the glue and wait 10 seconds.

3. Removal of the old battery

The battery in the Redmi 4A is glued to the body with double-sided tape to remove it.

1. Put a plastic shoulder blade on the battery from any angle.
2. Pull up slowly, putting on the perimeter. If you resist, put alcohol under the edge (not on the battery itself!).
3. Do not use metal tools or puncture the battery – this can cause fire.

After extraction, clean the case of glue residues with alcohol. If the new battery does not have adhesive base, buy a double-sided tape 0.5 mm thick (for example, 3M 9448A).

Installation of a new battery

Before you install, compare the new battery to the old one: the connector must match the location and number of contacts.

1. Stick the new battery onto a double-sided scotch (or use the original adhesive base if you have one).
2. Connect the battery connector to the motherboard. It should click with a click.
3. Connect the power button plume (if turned off).
4. Make sure all cables are flat and not covered.

Don't turn on your smartphone right away! First, put the case back together and check if you've forgotten to plug something in.

5. Build a smartphone

Collect Redmi 4A in reverse order:

1. Lay the fingerprint scanner plume (if any) and secure the cover with two screws.
2. Click the lid, starting at the top (where the camera is) and gradually pressing it around the perimeter.
3. Put it in. SIM-memory-card.

After assembly, plug in the charging and wait for the charging indicator to appear. If the smartphone does not turn on, check the connection of the plumes and battery connector.

💡

After replacing the battery, perform 2-3 full discharge/charging cycles (0% to 100%) to calibrate the battery controller, which will help to accurately display the charge level.

Frequent Mistakes and How to Avoid Them

Even with a careful replacement, you can make mistakes that will cause your smartphone to fail.

• 🔌 The battery connector is not connected correctly, and if you confuse the polarity (although the connector is made foolproof), the smartphone won't turn on. Solution: check the labeling. + and on the battery and board.
• 🔧 Clutched plumes - if the lid is pressing on the cables, the screen may stop working or a "glutty" touchscreen appears.Solution: make sure the plumes are lying loose.
• 🔥 Battery damage - punctures or severe deformities when extracted can cause electrolyte leakage.Solution: use only plastic tools.
• 📱 Poor battery – cheap analogues can not hold the charge or swell in a month.Solution: buy proven brands (see table above).

If the smartphone does not turn on after replacing, but the charging is underway (the indicator is burning), try holding the power button for 20-30 seconds. If there is no reaction, check the connection of the power button plume or contact the service.

💡

The most common cause of failure after replacement is a disconnected power button plume. Always check its connection first!

Calibration of the new battery

The new battery requires a run-in so that the charge controller can more accurately determine its capacity.

1. Charge your smartphone to 100% and leave on charging for another 1-2 hours.
2. Turn off charging and use the phone until it is completely discharged (until it turns off itself).
3. Repeat the charging/discharge cycle 2-3 times.

After calibration, check the actual capacity in the AccuBattery app (should be close to 3120 mAh). If the capacity is much lower, the battery is defective or fake.

We also recommend turning off battery optimization for critical applications (Settings → Battery → Battery Optimization) so that they do not close the background and do not interfere with calibration.

The cost of replacement in the service vs independently

If you're not sure about your own abilities, you can go to the service center.

It depends on your confidence and your budget. If your smartphone is your main device and you're afraid of damaging it, you'd better pay more for the service. If you have experience disassembling the equipment or take a risk, replacing it yourself can save up to 1,000 rubles.

FAQ: Frequent questions about battery replacement